In the automotive battery field, automotive technicians use battery clamps to electrically connect a battery to a charging/testing device. According to some embodiments, it is important for these battery clamps to have a secure physical and a secure electrical connection with the battery's terminals. A poor connection can result in damage to the battery, damage to the charging/testing device, injury to the operator, and it can impact the accuracy of test results. For example, poor connections can lead to the generation of heat, which can cause the battery terminals to melt and possibly cause the battery to explode in some cases.
Generally there are three types of automotive batteries: (1) top post terminal batteries, (2) side post terminal batteries, and (3) dual post terminal batteries (e.g. universal fit-type batteries). Top post terminal batteries include two lead post terminals that protrude upwardly from the top of the battery. Installing a top post terminal battery in a vehicle such as an automobile involves attaching electrical cables to each of the two lead post terminals. Even while a vehicle's electrical cables remain attached to a top post battery, the lead posts typically provide a sufficient surface for mechanically and electrically connecting a pair of standard battery clamps to perform a test and/or charge of the battery.
Side post terminal batteries, on the other hand, generally consist of two lead pad terminals on the side of the battery, each terminal having a threaded bore. The threaded bore is typically made of stainless steel to prevent corrosion of the battery terminal. Installing a side post terminal battery in a vehicle such as an automobile involves attaching electrical cables to each of the two lead pads using a steel bolt. The electrical cables generally have a loop attached to the end of the cable. The steel bolt fits through the loop and mates with the threaded bore portion of the terminal, keeping the cable in physical and electrical contact with the lead pad portion of the side post terminal battery.
Dual post terminal batteries are a combination of a top post terminal battery and a side post terminal battery. Dual post terminal batteries have four terminals, two on the top (e.g., top post terminals) and two on the side (e.g., side post terminals). Dual post terminal batteries are typically supplied with plastic or rubber covers to electrically insulate/cover the two terminals not in use.
To charge or test a top post terminal battery, for example, an automotive technician connects a pair of battery clamps onto two respective top post terminals protruding from the top of the battery. This traditional method of “clamping” a battery clamp onto each terminal is sufficient for testing/charging a top post terminal battery because there is typically enough surface area on the top post terminals to allow for a proper and secure connection, even when the battery remains connected to the vehicle.
To test or charge a side post terminal battery, for example, an automotive technician generally connects a pair of standard battery clamps onto steel bolts that hold a vehicle's electrical cables in contact with the side post terminals of the battery. While connecting standard battery clamps onto the steel bolts is possible, it is difficult and less accurate than other methods. Prior solutions to the minimal surface area problem involved, for example, an automotive technician disconnecting the steel bolts and electrical cables from the battery and using lead adapter posts. According to such a method, the technician screws a lead adapter post into each of the side post terminals of the battery. The lead adapter posts, when connected, essentially convert the side post terminal battery into a top post terminal battery, only having the posts on the side of the battery. The lead adapter posts are designed to provide a sufficient surface for attaching standard battery clamps. The technician can attach the lead adapter posts to the battery while the battery remains in the vehicle or after the battery has been removed from the vehicle.
However, lead adapter posts are small and are easily lost or misplaced in automotive repair/testing shops. Typically, when technicians lose or misplace their lead adapter posts, they often substitute a standard steel bolt to provide a method of attaching the standard battery clamps; however, the steel bolts only contact the threaded bore portion of the side post terminal. For example, FIG. 2a depicts a cross-sectional view of a side post battery 200 having a standard steel bolt 210 connected to a side post terminal 220. Noticeably, the steel bolt 210 does not physically contact the lead pad portion 222 of the side post terminal 220. Rather, the steel bolt 210 only makes contact with the stainless steel threaded bore portion 224 of the side post terminal 220. Such an arrangement can yield both inaccurate battery test results and also generate significant amounts of heat that can melt and destroy the side post battery 200. Conversely, FIG. 2b depicts a cross-sectional view of a side post battery 230 having a lead adapter post 240 connected to a side post terminal 250. Noticeably, the side post adapter 240 makes an electrical and physical connection with both a stainless steel threaded bore portion 254 and with a lead pad portion 252 of the side post terminal 250.
What is needed is a battery clamp that can easily, safely, and reliably connect to both top post terminal and side post terminal batteries without the necessity of an independent lead adapter post. What is also needed is a battery clamp that can connect to side post terminals and provide accurate battery testing results.